Not applicable.
Not applicable.
1. Field of the Invention
The present invention generally relates to a protective casing for an electrical connection. More particularly, the invention relates to a protective casing for a tee electrical connection typically found in various applications such as for seismic equipment. Still more particularly, the invention relates to keyed protective casing that can be removed and replaced without disconnection of the electrical connections housed within the tee connection.
2. Background Information
The field of seismology focuses on the use of artificially generated elastic waves to locate subsurface formations which may contain mineral deposits such as hydrocarbons, ores, water, and geothermal reservoirs. Seismology may also be used for archaeological purposes and for obtaining geological information for engineering. Exploration seismology provides data that, when used in conjunction with other available geophysical, borehole, and geological data, can provide information about the structure and distribution of rock types and their contents.
Seismic exploration involves attempting to deduce the subsurface geometry and properties of a portion of land. This typically is accomplished by generating seismic energy via impulse-type explosions or gentler vibrations, detecting the reflected and refracted seismic energy with appropriate detection devices, recording the measurements and processing the recorded information. The detection equipment generally includes a geophone or a plurality of geophones spaced apart in an array. The term xe2x80x9cgeophonexe2x80x9d is used throughout this disclosure to refer to any type of seismic detector. The geophones respond to vibrations from the earth and generate and transmit corresponding electrical signals to recording and processing equipment. An electrical cable couples one geophone to the next in the array.
FIG. 1 shows a schematic drawing of several geophones 10 coupled together by a cable 12. Each geophone connects to the cable 12 at a tee connection 14 (called a xe2x80x9cteexe2x80x9d connection because if its general resemblance to the letter xe2x80x9cTxe2x80x9d). Connection points 14 typically simply comprise electrical conductors and a circuit board that facilitates connecting the conductors together to form the tee connection. Connection points 14, as is true for most of the rest of the seismic detection equipment, are exposed to the elements in the field such as water, wind, and the like. These connections and their associated circuit boards must be protected and, accordingly, a protective covering or housing typically is provided on each tee connection to perform that function. Such a protective covering typically is referred to simply as a xe2x80x9ctee.xe2x80x9d For purposes of this disclosure, the electrical connection is referred to as a xe2x80x9ctee connectionxe2x80x9d and the protective covering is referred to simply as a xe2x80x9ctee.xe2x80x9d
A conventional tee is depicted in FIG. 2 and typically comprises two pieces 16 and 18 which are typically attached together with screws or similar fasteners to protect the connection. To install such a tee, the electrical cable 20 to the geophone 10 is inserted upward and through an opening in the bottom tee half 18. Then, the conductors in cable 20 are soldered to a circuit board in the tee connection point 14 to which the ends of cable 12 are also soldered. After the connections are soldered, the top tee half 16 is positioned over the lower half 18 and the two halves are placed together and attached by screws.
Although generally satisfactory, there is a significant disadvantage to the conventional two-piece tee shown in FIG. 2. If the bottom tee half 18 breaks, or for some other reason needs replacement, a labor intensive and time consuming task is necessary to replace the bottom tee half. To remove the bottom tee half, the two tee halves 16, 18 must first be disconnected from each other. Then, the electrical connections corresponding to cable 20 must be desoldered. Once cable 20 is disconnected from connection point 14, the broken bottom tee half 18 can be removed and replaced with a new piece. Then, the conductors associated with geophone cable 20 must be resoldered. Finally, the top half 16 must be reattached to the lower half. This entire process can take upwards of 15 to 20 minutes. On a seismic site having hundreds or thousands of tees, this process can be very time consuming and costly. Further, each time a solder joint is desoldered and resoldered, the mechanical and electrical integrity of the connection is diminished.
Accordingly, a solution to the aforementioned problem is needed. Such a solution would preferably permit quick removal and replacement of a tee and avoid the problems associated with desoldering and resoldering electrical connections.
The problems noted above are solved in large part by a three-piece keyway tee that comprises a cover and two lower pieces. Each lower piece preferably includes a protruding key and a key slot. The two lower pieces mate with one another, with the protruding key of each lower piece engaging the key slot of the other lower piece. The keys and slots preferably extend through an entire length of the lower pieces. In such an embodiment, mating the lower pieces together includes engaging the keys and slots and sliding one lower piece along an axis relative to the other lower piece. Preferably, the lower pieces are substantially identical.
According to one preferred embodiment, each lower piece has a groove along its length, such that when mated together, the grooves of the lower pieces align generally forming a passageway through which the geophone cable can extend up to the connection point 14. As such, the lower pieces surround the geophone cable when mated together. Thus, in contrast to conventional tee connection casings, the lower pieces of the preferred embodiment can be mated together without disconnecting any conductors from a three-way electrical tee connection. Similarly, the keyway tee can be removed and replaced with a new keyway tee without disconnecting any electrical connections. These and other advantages and benefits will become apparent upon reviewing the following disclosure.